How to change variables with time, Simulink

i'm using a varible to define the paramters of a switch in Simulink, I want this variable value to change after a period of time. I understand that I may not actually be able to change the value of a variable during a simulation but i'm not sure how to get around this, thanks.

Answer 1

[Fangjun Jiang]

The Switch block has only one parameter, the criteria used to compare with the second input. I would use a Relational Operator block to do the comparison and then use the Switch block. Your variable changes with time. It is a signal, not a parameter. Feed this signal to the Relational Operator block and the problem is solved.